1. Field of the Invention
This invention relates to a camera vibration correction apparatus, and more particularly to a camera vibration correction apparatus, which is capable of preventing blurring of an image caused by camera vibration.
2. Description of the Related Art
There have heretofore been made various proposals regarding the camera vibration correction apparatus for preventing blurring of an image on an image-formation surface, at which the focus is made, said blurring of an image being caused by the camera vibration and the like. This camera vibration correction apparatus is constituted by the following elements.
That is, a group of correcting lenses for correcting blurring of the image on the image-formation surface, at which the focus is made, is positioned in front or at the back of a group of photographic lenses, and a driving motor for moving the group of correcting lenses is connected to this group of correcting lenses. Connected to the driving motor is a CPU which controls the lens driving of the driving motor. Furthermore, connected to the CPU is an acceleration sensor for detecting the magnitude and directions of the camera vibration.
The CPU computes a correcting moving value to be given to the group of correcting lenses on the basis of information obtained from the acceleration sensor, and the information indicating the correcting movement value thus computed is output to the driving motor. Then, the driving motor moves the group of correcting lenses by a value negating a movement of the image caused by the camera vibration on the basis of the above-described information.
FIG. 7 shows a conventional camera vibration correction apparatus. A group of correcting lenses 1 is held by a lens frame 1A which is supported by a main body 5 of a camera through plate springs 2 and 2 secured to the right and left sides of the lens frame 1A, a ring 3 and plate springs 4 and 4 secured to the top and bottom sides of the ring 3. Secured to the lens frame 1A are a screw 5A and a motor 6A for rotating the screw. This motor 6A is driven, whereby the plate springs 2 and 2 are flexed to the right and left, so that the lens frame 1A can be moved to the right and left with respect to an optical axis P. Furthermore, the motor 6B for rotating the screw 5B, which is secured to the ring 3, is driven, whereby the plate springs 4 and 4 are flexed vertically, so that the lens frame 1A can be moved vertically with respect to the optical axis P.
The above-described motors 6A and 6B are driven on the basis of the information from the CPU, which is computed on the basis of camera vibration information obtained from an acceleration sensor, (not shown), so that the group correcting lenses 1 is vertically and laterally moved by a value negating the movement of the image caused by the camera vibration.
FIG. 8 shows another conventional camera vibration correction apparatus. The lens frame 1A holding the correcting optical system lens 1 is held in a tubular member 8 through four plate springs 7. Furthermore, secured onto the outer peripheral surface of the lens frame 1A are forward end portions of movement control bars 9A and 9B, whereby the lens frame 1A can be laterally moved with respect to the optical axis P by rocking the movement control bars 9A laterally. Moreover the lens frame 1A can be vertically moved with respect to the optical axis P by rocking the movement control bars 9B vertically.
The above-described movement control bars 9A and 9B are driven on the basis of the information of the camera vibration obtained from an acceleration sensor similar to the screw motors 6A and 6B, so that the group of correcting lenses 1 can be moved vertically and laterally by a value negating the movement of the image caused by the camera vibration.
However, in the conventional camera vibration correction apparatus, the camera vibration correcting function is operated and controlled in all of the regions from the wide angle side to the telescopic side during the zooming of the group of photographic lenses, so that disadvantages are present. First, the camera vibration correction apparatus is not correct, and second, the life of the battery of the camera vibration correction apparatus is shortened.
Furthermore, in the conventional camera vibration correction apparatus shown in FIGS. 7 and 8, the lens frame is supported by the plate springs, whereby the lens frame cannot be supported stably, and further, the motors or the movement control bars for moving the plate springs or the lens frame are provided separately of each other, thereby presenting the disadvantage of complicated construction.